The control of animal parasites is essential, especially in the areas of food production and companion animals. Existing methods of treatment and parasite control are being compromised due to growing resistance to current commercial parasiticides, such as the benzimidazoles and ivermectins. The discovery of more effective ways to control animal parasites is therefore imperative.
The literature has reported several derivatives of the 2-phenyl-3-(1H-pyrrol-2-yl)acrylonitrile ring system, that are based on Formula 1,
wherein R1 is not aryl or heteroaryl. These include 3-(2-pyrrolyl)-2-(4,5-dimethoxy-2-nitrophenyl)acrylonitrile and 3-(1-methyl-2-pyrrolyl)-2-(4,5-dimethoxy-2-nitrophenyl)acrylonitrile, described in J. Org. Chem., 30, 1965, 2553;3-(2-pyrrolyl)-2-(4-substitutedphenyl)acrylonitrile and 3-(1-methyl-2-pyrrolyl)-2-(4-substitutedphenyl)acrylonitrile derivatives. The para substituent is H, Me, MeO, Cl and NO2, described in J. Heterocyclic Chem., 23, 1986, 1747; 3-(2-pyrrolyl)-2-(4-substitutedphenyl)acrylonitrile and 3-(1-methyl-2-pyrroly)-2-(4-substitutedphenyl)acrylonitrile derivatives. The para substituent is H, Me, MeO, Cl and NO2, described in J. Liquid Chromatography, 7, 1984, 2631; 3-(2-pyrrolyl)-2-(phenyl)acrylonitrile, described in Tetrahedron, 45, 1989. 3-(2-pyrrolyl)-2-(4-substitutedphenyl)acrylonitrile and 3-(1-methyl-2-pyrrolyl)-2-(4-substitutedphenyl)acrylonitrile derivatives. The para substituent is H, Me, MeO, Cl and NO2, as described in Journal of Organic Chemistry, 1958, 23, 711-14;Some general synthetic routes to compounds of this type, such as 3-(2-pyrrolyl)-2-(phenyl)acrylonitrile, have been described (see, Journal of Organic Chemistry, 1958, 23, 711-14, cited above).
However, previously reported methods of using compounds of this type are limited to cough suppression and the materials sciences, e.g., as light absorbing agents, including, 3-(2-pyrrolyl)-2-(4,5-dimethoxy-2-nitrophenyl)acrylonitrile, and
3-(1-methyl-2-pyrrolyl)-2-(4,5-dimethoxy-2-nitrophenyl)acrylonitrile, as described by U.S. Pat. Nos. 3,370,063, 3,381,006, 3,454,586, 3,467,670 and 3,491,114, and as photosensitive dyes, as described by JP5100264 and JP6190165. JP 6190165 describes 3-(2-pyrrolyl)-2-phenylacrylonitrile derivatives that contain nitro and/or amino substituent at the para position of the phenyl ring and the 5 position of the pyrrole. In particular, cough suppression is the only biological activity reported for phenyl pyrrole acrylonitriles of Formula 1, wherein R1 is not aryl or heteroaryl [Compt. Rend., 259, 1964, 4716-18, describing 3-(1-ethyl-2-pyrrolyl)-2-(phenyl)acrylonitrile].
The citation of any reference herein should not be construed as an admission that such reference is available as “prior art” to the instant application.